Safety device for elevators.



No. 795,341. PATENTED JULY 25, 1905. E. R. GARIGHOFF.

SAFETY DEVICE FOR ELEVATORS.

APPLIOATION FILED MAB. 8 1905.

M MZ ATTORNEY ANDREW a cnAH/m LO. Pnomumocmhmns WASHIMZTON. u v

ENTTE STATES PATENT @EFTCE.

SAFETY DEVICE FOR ELEVATORS.

Specification of Letters Patent.

Patented July 25, 1905.

Application filed March 8 1905. Serial No. 249,119.

To all whom, it 772/607] concern:

Be it known that I, EUGENE R. OARICHOFF, a citizen of the United States,residing at East Orange, in the county of Essex and State of New Jersey,have invented certain new and useful Improvements in Safety Devices forElevators, of which the following is a specification.

My invention relates to safety devices for elevators; and its object isto improve upon structures of this kind now in use and to provide adevice for quickly and. powerfully clamping an elevator-car to theguides over which it is adapted to run.

I will describe my invention in the following specilication and pointout the novel features thereof in claims.

Referring to the drawings, Figure 1 is a diagrammatic view in elevationof an elevator-car and certain connected apparatus which may be used incarrying out my invention. Fig. 2 is a plan view, partly in section, ofmy safety device, showing sections of the guides which it is intended toclamp. Fig. 3 is a plan view of a modification of my invention, and Fig.4 is a side elevation of the device shown in Fig. 3.

Like characters of reference designate corresponding parts in all of thefigures.

1O designates an elevator-car to the bottom of which my device isattached.

11 is a hoisting-rope for the car.

12 is a governor-rope connected to run with the car. This governor-roperuns under a sheave 13, situated near one end of the cars travel. It maybe weighted, as at 15, and pawls 16 16 may be provided, if desired, toengage with ratchets in the sides of the weight 15 to prevent its upwardmovement. The governor-rope 12 runs over another sheave 14 near theother end of the cars travel, which is connected to a governor orspeed-regulator 17 by suitable gearing 18. The speed-governor isarranged to actuate a gripping device 19, which grips and positivelylocks the governor-rope whenever the car runs in eX- cess of normalspeed. It may be regulated or set to operate at any desired speed andmay be arranged to operate when the car is running in either direction.The governorrope is yieldingly connected to the car at 12 and is soarranged that when the governorrope 12 is stopped and the car continuesto move it will pull away from the yielding connection. This will causethe rope 12, which is attached to the governor-rope 12, to be pulledthrough the pulleys 12 12 and to be unwound from a drum 31 on the safetydevice, and thereby impart a rotary motion to the winding-drum 31. It issometimes desirable to rotate the winding-drum 31 by hand from the car,and for this purpose I have provided another rope 12 on the winding-drumand attached this rope to a handle 12 within reach of the operator inthe car.

I will now refer to Fig. 2 and describe the clamping device or safetydevice for the elevator-car, which is there illustrated. Thewinding-drum 31 is rotatably supported by brackets 34 34, which arerigidly mounted upon a frame 30 30, which holds the safety device andwhich is preferably attached to the bottom of an elevator-car. The drum31 may be grooved, as shown at 32, for the reception of the ropes 12 and12 which are attached to it. The inside of the drum is provided withright and left hand screwthreads in which screws 35 and 36 work. Theouter ends of these screws are attached to floating levers 37 and '38,as shown at 35 and 36, respectively. The other ends of these floatinglevers are connected to a spring-actuating mechanism 40 at 37 and 38.This mechanism comprises a spring 41, which is preferably underconsiderable compression, and two end pieces 42 and 43, which areprovided with collars 42 and 43, which abut against the spring 41. Thisspring-actuating mechanism has a tendency to spread the floating levers37 and 38 apart, but is prevented under ordinary conditions from doingso by an adjustable locking-arm 44. This locking-arm 44 is threaded onone end 45, and this end passes through the floating lever 37 and may beprovided with ad justing-nuts 46 46. The other end of the locking-arm 44is provided with a ratchet 47, which is adapted to engage with a pin 47on the lever38. The locking-arm also carries a tripping-piece 48, whichis pivoted at 49 and which bears against one of a series of pins 33 33,which are provided on one end of the winding-drum 31 for this purpose,and against the pin 47 on the locking-arm 44.

At 27 and 28 are attached rods 26 26, on the other end of whichwedge-shaped cams are provided. These cams 25 are adapted to be forcedbetween the antifriction-rollers 24 24, which are provided near the endsof gripping-jaws 21 21, which are pivoted at 23 23 to the frame 30 andthe other ends of which are arranged and adapted to clamp the uprightguides 22 22.

I will now describe the operation of my device. iVhenever the carattains undue speed,- so that the governor acts and causes the rope 12to be pulled in the manner previously described, the winding-drum 31will be turned thereby. The first effect of this movement of the drumwill be to remove the one of the pins 33 33 against which thereleasing-piece 48 has been pressing from the releasing-piece 4:8. Thelatter will then be free to move from its locking position and willallow the spring 41 to spread the floating levers 37 and 38 quicklyapart. The wedge-shaped cams 25 25 as they are connected to these leversby the rods 26 26 will be forced by this movement between the rollers24: 24 on the ends of the clamps 21 and will thus cause the clamps to bemoved against and to grip the guides 22 22. The pin 47 on the floatinglever 38 will engage the ratchet 47 and positively hold the levers apartin the position into which they have been forced by the spring 4C1. Upona further movement of the winding-drum 31 the right and left hand screws35 and 36 will be forced outward and through their connected parts willforce the clamps 21 21 against the guides 22 22 with great power. Itwill be seen then that in this arrangement an ideal elevator safety-stophas been provided, for upon the slightest movement of the windingdrum31, which movement may be obtained automatically or by hand, theclamping device is immediately forced against the guides and itsretarding effect at once brought into action, and that this retardingeffect is then increased bya positive mechanical movement without theintervention of springs or other yielding mechanism until the car isbrought to rest. Then of course the movement of the winding-drum 31ceases.

The various parts may be reset by hand. If desired, springs maybeprovided to hold the clamps 21 21 away from the guides when not forcedon by the above-described mechanism. I have provided a projection 47 atthe end of the rachet 47 to prevent the floating levers 37 and 38 fromcoming nearer together than a certain predetermined distance, which maybe regulated by the adjusting-nuts 4L6 4:6 on the other end of thelocking-arm ll. This serves a double purpose. First, it makes itpossible to limit the distance which the clamps may be moved from theguides; second, it makes the part of the safety device which is actuatedby the right and left hand screws 35 36 a complete and operative devicein itself, and it will operate to apply the clamps to the guides even ifthe spring-actuating mechanism &0 should become disabled.

- I will now describe the modification of my invention which isillustrated in Figs. 3 and 1. In this case the wedge-shaped cams 25' 25are attached to arms 26' 26, on which gears 50 are pivoted. The insideends of these arms are bent up at right angles, as shown. To one of thema locking-bar 44 is connected, to the other end of which atripping-piece 48' is attached. The other end of the tripping-piecebears against the other arm 26. The rope 12 is in this case attacheddirectly to the tripping-piece 48 without the this intervention of anywinding-drum. In case there are two spring-actuating mechanisms, one ofwhich comprises a spring 55, which bears against collars 56 56 on thearms 54 54:. These arms are each provided with a rack 51, which engageswith one of the gears 50 50, and a ratchet 52, into which a pawl 53works. It is evident that when the tripping-piece L8 is released by apull on the rope 12" and the locking-arm 44 is released thereby thespring will then force the arms 54 54 apart and through their connectedmechanism will move the cams 25 25 apart. These cams may be arranged tomove clamps against the elevator-guides, as before described. The spring55 is preferably made comparatively light and quick-acting, so that itwill move the clamps against the guides almost instantaneously. After ithas thus forced the arms 54: 54 apart the latter are prevented fromreturning to their first position by the ratchet-and-pawl arrangementshown. Another spring is shown, which acts in substantially the sameway; but this spring is preferably made heavy and powerful, so that itwill move the arms 6e 6% and the cams 25 25 apart with great force. Itis, however, surrounded by a cylinder 60, closed at its ends, as shownat 62 62, and the collars 66 66 on the arms 64 64 form pistons whichwork in the cylinder 60. The cylinder may be filled with oil andarranged to act as a dash-pot or retarding device for the spring 65.Holes 63 63 may be provided in the pistons 66 66 to allow for thecirculation of the oil and to regulate the speed of the pistons travel.It may be seen then that the action of the spring 65 will be slow butpowerful. When the tripping-piece 48' is moved to release the parts, thespring 55 will immediately move the clamps against the elevator-guides,so that their retarding effect will be at once effective, and the spring65 will then slowly increase this retarding effect with great force. Thespring 55 may not be powerful enough to stop the car; but the spring 65should be strong enough to stop the car with maximum load traveling atany speed. This arrangement provides an ideal safety-stop for elevators,as its action is quick; but it will bring the car to rest gently.

\Vhat I claim is-- 1. In a safety device for elevators, the combinationof a car, guides for the car, a clamping device for the car, means forquickly moving the clamping device to the guides, a lock to prevent theclamping device from moving back from the guides, and additional meansarranged to tighten the clamping device on the guides.

2. In a safety device for elevators, the combination of a car, guidesfor the car, a clamping device for the car, spring-actuating mechanismfor the clamping device, a lock arranged to prevent the clamping devicefrom moving back from the guides, and additional means arranged totighten the clamping device on the guides.

3. In a safety device for elevators, the combination of a car, guidesfor the car, a clamping device'for thecar, spring-actuating mechanismfor moving the clamping device in one direction, a lock arranged toprevent the spring-actuating mechanism from moving in but one direction,and means arranged to tighten the clamping device on the guides.

at. In a safety device for elevators, the combination of a car, guidesover which the car is adapted to run, a clamping device on the car, aspring arranged to move the clamping device against the guides, a lockto hold the clamping device against the guides, and a screw arranged totighten said clamping de vice on the guides.

5. In a safety device for elevators, the combination of a car, guidesover which the caris adapted to run, a clamping device on the car, aspring arranged to move the clamping device against the guides, a lockto hold the clamping device against the guides, a screw arranged totighten said clamping device on the guides, and means for actuating thespring and the screw.

6. In a safety device for elevators, the combination of a car, guidesover which the car is adapted to run, a clamping device on thecar, aspring normally held under compression arranged to move the clampingdevice against the guides when released, a holding device for thespring, means for locking the spring mechanism after it has acted, ascrew arranged to tighten the clamping device on the guides, and meansfor actuating the screw and releasing the spring.

7. In a safety device for elevators, the combination of a car, guidesover which the car is adapted to run, a clamping device on the car,

, a spring normally held under compression arranged to move the clampingdevice against the guides when released, an adjustable holding devicefor the spring, a ratchet to lock the spring mechanism after it hasacted, a screw arranged to tighten the clamping device on the guides,and means for actuating the screw and thereby releasing the spring.

8. In a safety device for elevators, the combination of, a car, guidesover which the car is adapted to run, a clamping device on the car, aspring arranged to move the clamping device against the guides, a lockto hold the clamping device against the guides, a screw arranged totighten said clamping device on the guides, and means for actuating thespring and the screw by the motion of the car.

9. In a safety device for elevators, the combination of a car, guidesover which the car is adapted to run, a clamping device on the car, aspring arranged to move the clamping device against the guides, a lockto hold the clamping device against the guides, a screw arranged totighten said clamping device on the guides, means for actuating thespring and the screw when the speed of the car reaches a predeterminedlimit and means for actuating the spring and the screw by hand.

10. In a safety device for elevators, the combination of a car, guidesover which the car is adapted to run, a clamping device on the car, aspring arranged to move the clamping device against the guides, meansfor retaining the clamping device against the guides, a screw arrangedto tighten said clamping device on the guides, and a governor connectedto run with the car and arranged to actuate the screw and to release thespring when the speed of the car reaches a predetermined limit.

1l. In a safety device for elevators, the combination of a car, guidesover which the car is adapted to run, clamping devices on the car, aspring arranged to move the clamping devices against the guides, meansfor retaining the clamping devices against the guides, and right andleft hand screws arranged to tighten said clamping devices on theguides.

12. In a safety device for elevators, the combination of a car, guidesover which the car is adapted to run, clamping devices on the car, aspring arranged to move the clamping devices against the guides, meansfor retaining the clamping devices against the guides, right and lefthand screws arranged to tighten said clamping devices on the guides, andmeans for actuating the spring and the screws.

13. In a safety device for elevators, the combination of a car, guidesover which the car is adapted to run, clamping devices on the car, aspring arranged to move the clamping devices against the guides, meansfor retaining the clamping devices against the guides, right and lefthand screws arranged to tighten said clamping devices on the guides, anda governor arranged to actuate the spring and the screws by the movementofthe car when the speed of the car reaches a predetermined limit.

14. In a safety device for elevators, the combination of a car, guidesover which the car is adapted to run, clamping devices on the car, aspring arranged to move the clamping devices against the guides, meansfor retaining the clamping devices against the guides, right and lefthand screws arranged to my name in the presence of two subscribingWitnesses.

EUGENE R. CARIOHOFF.

Witnesses: v

JOSEPH E. GAVANAUGH, ERNEST W. MARSHALL.

